1. Field of the Invention
The invention relates to a radio frequency identification tag device, more particularly to a radio frequency identification tag device for metallic products.
2. Description of the Related Art
Generally, a radio frequency identification (RFID) system includes an RFID tag device, serving as a transponder, adapted to be installed on a product, a RFID reader, serving as an interrogator, communicating with the RFID tag device in a wireless manner, and a system main unit, such as a host computer, coupled to the RFID reader.
In actual use, a conventional RFID tag device for metallic products is expensive, and has a relatively large size. On the other hand, although a conventional RFID tag device for non-metallic products is cheaper than that for metallic products, an effective communication distance between the conventional RFID tag device and the RFID reader is relatively short. If the conventional RFID tag device for non-metallic products is attached to a metallic product to reduce costs, a read request signal radiated by the RFID reader is easily reflected by the metallic product as a result of the image current effect. As a result, the conventional RFID tag device for non-metallic products cannot be directly attached to a metallic product.